December 29, 1906

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Features

The President's Message on the Panama Canal

Present Condition of the New York Tunnels

William Henry Welch

By Marous Benjamin

Catechism of a Scientist

The "Unilens" a Novel Form of Telescope

By the English Correspondent of the Scientific American

The New Lusol Lamp

By Jacques Boyer

A Simple Experimental Dynamo

By Paul H. Woodruff

The Solution of New York's Transportation Problem

The Apparatus of the United States Life-Saving Service

By Waldon Fawcett

Eye-Spotting in Nature

By Percy Collins

Increasing the Power of a Talking Machine by Means of Compressed Air

Business and Personal Wants

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Departments

Departments

Correspondence

Recently Patented Inventions

Notes and Queries

Index of Inventions

New Books, Etc.

Patents

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